Scarifier for use with asphalt concrete roadway refinishing apparatus

Claim 2

A scarifier assembly for engagement with a road surface to excavate the road surface, comprising: a support frame adapted to be moved over the road surface in a given direction, a plurality of scarifying blade units secured to said support frame for separate selective upward and downward movement and positioned to have cutting tips thereof engageable with the road surface when in the down position during a scarifying operation, and a plurality of discrete yieldable fluid operated pressure applying means positioned beneath said support frame and directly over said plurality of scarifying blades to apply a downward pressure directly upon said scarifying blades during the sacrifying operation.

Claim 3

The scarifier assembly for engagement with a road surface to excavate the road surface as set forth in claim 1 wherein said plurality of scarifying blade units comprise groups of blades in a row across said support frame, said row being transverse to the direction of travel of said support frame.

Claim 4

The scarifier assembly for assembly with the road surface to excavate the road surface as set forth in claim 1 wherein each of said discrete yieldable pressure units is an air bag.

Claim 5

The scarifier assembly for engagement with the road surface to excavate the road surface as set forth in claim 1 wherein each of said groups of scarifying blades is formed of three rows of three blades in each row aligned transversely to the direction of travel of said support frame and each row staggered from the other rows to allow excavated road material easily to pass through the scarifying blades as it travels in said given direction.

Claim 6

The scarifier assembly for engagement with the road surface to excavate the road surface as set forth in claim 1 further including fluid pressure control means for controlling the pressure produced by each of the said plurality of discrete yieldable pressure units, said pressure control means including means for controlling the fluid pressure produced by the two endmost discrete yieldable pressure units independent of the discrete yieldable units therebetween.

Claim 7

The scarifier assembly for engagement with the road surface to excavate the road surface as set forth in claim 5 wherein said discrete pressure units between said two endmost units are operated from a common pressure supply, and including valve means connected between said common pressure supply and said discrete yieldable pressure units, whereby selected ones of said pressure units can be deactivated.

Claim 8

The scarifier assembly for engagement with a road surface to excavate the road surface as set forth in Claim 1 wherein said scarifying blades include shear pin means for holding said scarifying blades in a fixed position during a scarifying operation and to permit rearward pivotal movement of said scarifying blade when a predetermined high shear pressure is exerted on said scarifying blade.

Claim 9

The scarifier assembly for engagement with a road surface to excavate the road surface as set forth in claim 1 further including joint cutting blade means positioned transversely outwardly of the endmost scarifying blades to remove road resurfacing material from the seam formed along the transverse edges of a repaved road surface to be formed.

Claim 10

The scarifier assembly for engagement with a road surface to excavate the road surface as set forth in claim 1 wherein said scarifying blades each include a cutting tip insert element of hardened metal.

Claim 11

A scarifier assembly for engagement with a road surface to excavate the road surface, comprising: a support frame adapted to be moved over the road surface in a given dIrection, a plurality of scarifying blades secured to said support frame for selective upward and downward movement and positioned to have cutting tips thereof engageable with the road surface when in the down position during a scarifying operation, yieldable pressure applying means positioned beneath said support frame and directly over said plurality of scarifying blades to apply a downward pressure directly upon said scarifying blades during the scarifying operation, a plurality of arm means each having one end pivotally secured to said support frame, said plurality of scarifying blades being arranged in groups, each group secured to the free end of an independent one of said plurality of arm means, a pressure beam secured to said support frame immediately above said free end of said arm means, and pressure bag means positioned between said pressure beam and said free end of said arm means to urge the scarifying blades into the road surface being excavated.

Claim 12

A scarifier assembly for engagement with a road surface to excavate the road surface, comprising: a support frame adapted to be moved over the road surface in a given dIrection, a plurality of scarifying blades secured to said support frame for selective upward and downward movement and positioned to have cutting tips thereof engageable with the road surface when in the down position during a scarifying operation, yieldable pressure applying means positioned beneath said support frame and directly over said plurality of scarifying blades to apply a downward pressure directly upon said scarifying blades during the scarifying operation, a plurality of arm means each having one end pivotally secured to said support frame, said plurality of scarifying blades being arranged in groups, each group secured to the free end of an independent one of said plurality of arm means, a pressure beam secured to said support frame immediately above said free end of said arm means, and pressure bag means positioned between said pressure beam and said free end of said arm means to urge the scarifying blades into the road surface being excavated.

Claim 13

The scarifier assembly for engagement with the road surface to excavate the road surface as set forth in claim 10 further including a plurality of paired spaced apart support plates depending from said free end of said arm means, said scarifying blades being positioned between said support plates, a first fastener of predetermined diameter passing through said support plates and the upper end of said scarifying blade, a second fastener of a diameter less than said predetermined diameter passing through said support plates and said scarifying blade immediately below said first fastener, whereby an excess of pressure applied to said scarifying blade will shear said second diameter fastener and pivot the scarifying blade about said first fastener.

Claim 14

The scarifier assembly for engagement with a road surface to excavate the road surface as set forth in claim 11 further including a plurality of spring means for automatically biasing said arms upwardly to raise the scarifying blade from the road surface when the pressure applying units are deactivated.

Claim 15

The scarifier assembly for engagement with a road surface to excavate the road surface as set forth in claim 12 wherein said spring means are a plurality of discrete leaf springs for each one of said arm means.

Claim 16

A road scarifier apparatus for excavating a road surface comprising in combination: heating means for movement over the road surface to soften asphalt concrete pavement forming the road surface, a support frame for supporting said heating means, said support frame adapted to be moved over the road surface in a given direction, a plurality of scarifying blade units secured to said support frame behind said heating means for separate selective upward and downward movement and positioned to have cutting tips thereof engageable with the heated road surface when in the down position for excavating the road surface, and a plurality of discrete separately yieldable fluid operated pressure applying units positioned beneath said support frame and respectively directly over said plurality of scarifying blade units separately to apply a downward pressure directly upon the scarifying blade units during a scarifying operation.

Claim 17

A road scarifier apparatus for excavating a road surface comprising in combination: heating means for movement over the road surface to soften asphalt concrete pavement forming the road surface, a support frame for supporting said heating means, said support frame adapted to be moved over the road surface in a given direction, a plurality of scarifying blade units secured to said support frame behind said heating means for separate selective upward and downward movement and positioned to have cutting tips thereof engageable with the heated road surface when in the down position for excavating the road surface, and a plurality of discrete separately yieldable fluid operated pressure applying units positioned beneath said support frame and respectively directly over said plurality of scarifying blade units separately to apply a downward pressure directly upon the scarifying blade units during a scarifying operation.

Claim 18

The road scarifier apparatus for excavating a road surface as set forth in claim 14, further including fluid pressure control means for controlling the pressure produced by each of said yieldable plurality of discrete pressure units, said pressure control means including means for controlling the pressure produced by the two endmost discrete yieldable pressure units independent of the discrete pressure units therebetween.

Claim 19

The road scarifier apparatus for excavating a road surface as set forth in claim 15, wherein said discrete yieldable pressure units between said two endmost units are operated from a common pressure supply, and including valve means connected between said common pressure supply and said discrete yieldable pressure units, whereby selected ones of said pressure units can be de-activated.

Claim 20

The road scArifier apparatus for excavating a road surface as set forth in claim 14, wherein said scarifying blades include shear pin means for holding the scarifying blades in a fixed position during a scarifying operation and to permit rearward pivotal movement of the scarifying blades when a predetermined high shear pressure is exerted on the scarifying blades.

Claim 21

The road scarifier apparatus for excavating a road surface as set forth in claim 14 wherein each of said discrete pressure units is an air bag.

Claim 22

The road scarifier apparatus for excavating a road surface as set forth in claim 14, further including joint cutting blade means positioned transversely outwardly of the endmost scarifying blades to remove the road resurfacing material from the seam formed along the transverse edges of the repaved road surface formed by said apparatus.

Claim 23

The road scarifier apparatus for excavating a road surface as set forth in claim 14, wherein said scarifying blades each include a cutting tip insert element of hard metal.

Claim 24

A road scarifier apparatus for excavating a road surface comprising in combination: heating means for movement over the road surface to soften asphalt concrete pavement forming the road surface, a support frame for supporting said heating means, said support frame adapted to be moved over the road surface in a given direction, a plurality of scarifying blades secured to said support frame behine said heating means for selective upward and downward movement and positioned to have cutting tips thereof engageable with the heated road surface when in the down position for excavating the road surface, yieldable pressure applying means positioned beneath said support frame and directly over said plurality of scarifying blades for applying a downward pressure directly upon the scarifying blades during a scarifying operation, a plurality of arm means each having one end thereof pivotally secured to said support frame, said plurality of scarifying blades being arranged in groups, each group secured to the free end of an independent one of said plurality of arm means, a pressure beam secured to said support frame immediately above said free end of said arm means, and pressure bags positioned between said pressure beam and said free end of said arm means to apply pneumatic pressure between said pressure means and the end of said arm means to urge the scarifying blades into firm contact with the road surface being excavated.

Claim 25

A road scarifier apparatus for excavating a road surface comprising in combination: heating means for movement over the road surface to soften asphalt concrete pavement forming the road surface, a support frame for supporting said heating means, said support frame adapted to be moved over the road surface in a given direction, a plurality of scarifying blades secured to said support frame behine said heating means for selective upward and downward movement and positioned to have cutting tips thereof engageable with the heated road surface when in the down position for excavating the road surface, yieldable pressure applying means positioned beneath said support frame and directly over said plurality of scarifying blades for applying a downward pressure directly upon the scarifying blades during a scarifying operation, a plurality of arm means each having one end thereof pivotally secured to said support frame, said plurality of scarifying blades being arranged in groups, each group secured to the free end of an independent one of said plurality of arm means, a pressure beam secured to said support frame immediately above said free end of said arm means, and pressure bags positioned between said pressure beam and said free end of said arm means to apply pneumatic pressure between said pressure means and the end of said arm means to urge the scarifying blades into firm contact with the road surface being excavated.

Claim 26

The road scarifier apparatus for excavating a road surface as set forth in claim 21 further including a plurality of paired spaced apart support plates depending from said free end of said arm means, said scarifying blades being positioned between said support plates, a first fastener of predetermined dimension passing through said support plates and the upper end of said scarifying blade, a second fastener of a dimension less than said predetermined dimension passing through said support plates and said scarifying blade immediately below said fastener, whereby an excess of pressure applied to said scarifying blade will shear said second fastener and pivot the scarifying blade about said first fastener.

Claim 27

The road scarifier apparatus for excavating a road surface as set forth in claim 22 further including a plurality of spring means for automatically biasing said arms upwardly to raise the scarifying blades from the road surface when the pressure applying units are de-activated.

Claim 28

The road scarifier apparatus for excavating a road surface as set forth in claim 23, wherein said spring means are a plurality of discrete leaf springs, each leaf spring associated with its associated arm means.

Claim 29

The road scarifier apparatus for excavating a road surface as set forth in claim 15, which includes fluid pressure control means associated with said yieldable pressure control means, said pressure control means having means to control the pressure of the endmost units of the scarifying blades independent of control of the units theRebetween, said control means further including means for deactivating selected ones of said plurality of units including said endmost units of scarifying blades.